Assistant Professor Tohoku University Sendai, Japan
Abstract: [Background] The bioengineered artificial organ can solve the problems around the current transplantation medicine, such as donor shortage and heterogeneous organ quality. If patient-specific cells are available for organ engineering, we could even overcome graft rejection after organ transplantation, which is particularly challenging in lung transplantation. This ambitious goal is only achievable after isolating and propagating the individual components of the target organ cells. However, we still lack the method to expand the highly diverse lung cell population at scale. Recently, researchers have investigated the potential role of Yamanaka reprograming factors for “rejuvenation.” The idea is to ectopically express reprogramming factors in adult cells to reverse the biological clock. This can be translated into creating a fetal-type progenitor cells using patient-specific cells. The aim of the current study is to transform the terminally differentiated adult cells into highly proliferative but lineage-restricted progenitor-type cells by transfecting Yamanaka reprogramming factors yet only transiently enough to avoid pluripotency. [METHODS] Human umbilical code vein endothelial cells (HUVECs) and small airway epithelial cells (SAEC) were purchased from Lonza. mRNA cocktail coding human Oct4, Sox2, Klf4, c-Myc, Nanog, and Lin28 (OSKMNL, Stemgent) were transfected to these cells with Lipofectamine MessengerMAX(ThermoFisher) for 2 to 4 days. Cells were either directly passaged to the next dishes or colony-picked. After passage, the cells were subjected to the organ culture using decellularized mouse lung scaffold and perfusion-based bioreactor. [Results and Discussion] This “partial” reprogramming using an mRNA cocktail converted human primary cells into a highly proliferating state with loss of mature endothelial/epithelial markers such as CD31 or Surfactant protein B. These reprogrammed cells formed “shiny” colonies similar to induced pluripotent stem cells; however, the cells spontaneously recovered some of the original phenotypes after just changing the media to the original cell-specific media such as EBM2 or SAGM. Finally, these reprogrammed “progenitor-like cells” seemed to recapitulate cellular heterogeneity in the mouse lung scaffold.
Funding Source: Grant-in-Aid for Scientific Research / KAKENHI (C) #20K09174, #23K08308, the Fund for the Promotion of Joint International Research (Fostering Joint International Research (B)) #22KK0132 for TS
